PROJECT SUMMARY/ABSTRACT The prevalence of cardiovascular disease (CVD) among U.S. adults under the age of 60 is nearly 40%. Coinciding with age-related declines in physical activity (PA), nearly half of mid-life adults also report insufficient sleep. As physical inactivity and poor sleep are independently associated with CVD risk factors including hypertension, multi-component interventions aiming to increase PA and improve sleep can evoke synergistic improvements in CVD risk. Augmenting the delivery of individually tailored behavior change techniques and behavioral feedback within ?smart? platforms can enhance user engagement and motivation that lead to improved PA and sleep behaviors. Our long-term goal is to advance the current science by integrating mobile and wearable technology within a comprehensive, bi-directional feedback system that can autonomously deliver behavioral interventions to improve cardiovascular health throughout the lifespan. The objective of this proposed research is to develop, test, and refine a cloud-based feedback system, and then evaluate the impact of a 3 month randomized feasibility pilot intervention ? the Bio-behavioral Systems to Motivate And Reinforce HearT Health (Be SMART) on changes in MVPA and sleep that will be used to inform a larger randomized control trial. The central hypothesis is that exposure to the Be SMART condition will lead to a sustained increase in weekly minutes of moderate-to-vigorous physical activity (MVPA) and improved sleep versus those assigned to an active control (Fitbit-only). The rationale for this research is supported by recommended approaches that include targeting individual lifestyle behaviors and providing continuous monitoring and real-time detection of clinical measures and biomarkers. Our central hypothesis will be tested by pursuing three specific aims. Aim 1 will examine the acceptability of the Be SMART feedback system by conducting a 6-week proof-of-concept study in mid-life adults. Aim 2 will quantify the impact of the Be SMART intervention on changes in MVPA and sleep metrics relative to a Fitbit-only condition among mid-life adults. Aim 3 will explore the extent to which changes in MVPA and sleep metrics impact blood pressure changes among mid-life adults. Secondly, we will quantify the extent to which Be SMART participants achieve their weekly goals and if goal achievement impacts changes in blood pressure. We propose a highly innovative study that will integrate and build upon existing technology within an automated, individually tailored feedback system designed to detect and respond to the extent to which weekly goal-oriented behaviors are achieved based on sound theory, motivational interviewing techniques and positive inquiry. The proposed research is significant because it addresses key risk behaviors for the prevention of early-onset CVD morbidity and mortality in mid-life adults. Moreover, this approach is readily extendable to other populations, settings, and health behaviors, with the potential to favorably impact public health and inform novel approaches to designing multi-component behavioral interventions.